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Determination on F and D with SU(3) symmetry breaking effects and Δs distributions in the nucleon

Determination on F and D with SU(3) symmetry breaking effects and Δs distributions in the nucleon. Teruya Yamanishi. § １　 Introduction. ● Data used numerical analyses for polarized quark distribution functions. － At LO QCD, first moment of pol. quark distribution functions. － F and D.

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Determination on F and D with SU(3) symmetry breaking effects and Δs distributions in the nucleon

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  1. Determination on F and D with SU(3) symmetry breaking effects and Δs distributions in the nucleon Teruya Yamanishi

  2. §１　Introduction ● Data used numerical analyses for polarized quark distribution functions －At LO QCD, first moment of pol. quark distribution functions

  3. －F and D Baryon semileptonic decays ; F and D for SU(3) flavor symmetry in these analyses Δs : negative and large ΔΣ : small Estimations of F and D with SU(3) and/or SU(2) breaking effects

  4. §2Baryon semileptonic decays ● Matrix element of V-A transition for M where

  5. ●Cabibbo model from N. Cabibbo et al., hep-ph/037298 .

  6. §3F and D with SU(3)and SU(2) flavor breaking ●In generally, g1(0) is expanded as with ●Here we take m = al + bl 3 8 as SU(2) and SU(3) breaking parameters.

  7. l Then, at Q2=0, one obtains for g1/ f1 : ・ There are 8 variables ;

  8. Experimental data of g1/ f1 :

  9. ●Total decay rate where and y and z are coefficients.CR is the radiative correction. ●In our calculations ―omit the form factors f3 and g3due to have terms of m/M. ―exclude g2in the framework of standard model because g2 arise from a “second class current”. ―express f2 in term of the anomalous magnetic moments of relevant baryons.

  10. l l l ●Data of Baryon semileptonic decays used in fitting * Rate in 10－3s－1

  11. ●Results

  12. ●SU(3) flavor symmetry case

  13. ●Both SU(3) and SU(2) flavor symmetry breaking case

  14. Σ－ n p Λ０ Σ＋ Σ0 Ξ－ Ξ0 ●Predictionsof the unmeasured measured unmeasured not used in fit no listed on PDG Taking into account the SU(2) flavor symmetry breaking * only g1 for Σ－→Λ and Σ＋→Λ

  15. Σ－ q = ± g cos 0 . 572 0 . 016 1 c n p Λ０ Σ＋ Σ0 Ξ－ Ξ0 ●Test of our results measured unmeasured not used in fit no listed on PDG by M. Bourquin, Z. Phys. C12, 307 (1982) .

  16. §4Δs content in the nucleon ●Nucleon spin content from Δs quarks ●ΔΣand Δs content from our results on F and D

  17. = ± = ± F 0 . 477 0 . 007 D 0 . 835 0 . 007 = ± F / D 0 . 572 0 . 010 = ± = ± D 0 . 793 0 . 005 F 0 . 475 0 . 004 SU(3) SU(3) = ± F / D 0 . 599 0 . 006 SU(3) §5Summary ●We have suggested a new formula for SU(3) structure constants F and D including SU(3) and SU(2) flavor symmetry breaking effects. ●Using present experimental data, g1/ f1 and decay rates, the numerical results for both SU(3) and SU(2) flavor symmetry breaking were compared with .

  18. ●The value of ( g1cosθc) for Σ－→Λ obtained from our results F and D with both SU(3) and SU(2) flavor symmetry breaking is consistent with the experimental data. ●At the LO of QCD, Δs becomes －0.188±0.055 for both SU(3) and SU(2) flavor symmetry breaking case, while that is －0.203±0.054 for SU(3) flavor symmetry case on the EMC result.

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